Thermostatic gas regulator



NMarch v19, 1929. F, W` SHUELL ET AL 1,705,787-

THERMOSTATI C GAS REGULATOR Filed Jan. 24, 1927 3513 [Qznerldbetter PatentedMar. 19, 1929.

UNiTED; STATES PATENT oFFicE.

FRANK W.

SI-IUECLL, ELMER. E.LE13BETTER, AND THOMAS J'. TOBEY, OF DETROIT,

,MICHIGAlW .ASSIGNORS TO THE EVERHOT HEATER" COMPANY, O-IEl DETROIT, MICHI-y GAN, A CORPORATION OF MICHIGAN.

THERMIOSTATIC Gris REGULATOR.

` Appiiation inea Januaryai, 1927'.A serial N. 163,222.

The invention relates to thermostatic gasV regulators and is particularly adapted for use in connection with an automatic'water heater.

The primary object of the invention is to provide a mechanism of simple construction, Which'is positive in action and eli'ective Yto variably regulate the flow of gas to the burner according to the .varyingtemperature of` the water adjacent the thermostatic element.l

Another objectv is to provide improved means for adjusting'the device to maintain I the water in the boilerat any predetermined temperature. 1

A further object is to prevent fluttering or chattering` or" the valve and also to prevent snap action'of the valve. l v

A further Obj ect is to obtain a construction in which the leverniechanism is housed within a shank projecting ironi the valve hous-l ing and means is provided for readily removing the valve without disturbing the ulcrum of the lever mechanism or the thermostatic element. y l

These and other objects are attained by providing the novel construction hereinafter described andl illustrated in the accompanying drawings, wherein l' y Figure 1 isy aloiigitudinal 'section v.through the regulating device;

Figure 2 is a section atrightfangles there-Y to on the line 2-2or" Figure 1; A

Figure 3 'is a topplan view partlyiiis'ecf` tion; i Figure l disk valve; Figure 5 yFig. 1. .7.

Figure 6 is al view at right angles to Fig. 5.

)referring now to the embodiment of our .in

is a section on -the line v{3j-5 o'l' vention illustrated in the drawings,.1 repre-4 sents the housing for the regulating mecha-l nism which as shown includes an annular. hol-- low portion 2 and a laterally extending sh ank 3, .preferably formed integral therewith. The housing is formed with the laterally cXtending threaded boss 4. which is apertured to form a inlet 5 'and is also `formed with a downwardly projecting boss 6 apertured t0 form the gais outlet 7 Theupper. end ot the annular portionlofthe housinglias a threaded opening 8 therein which is normally closed by a removable cap 9; Thezshank 3 has a threaded inner end 10 for engaging a spud11 welded tothe inner v'boiler'. shell,12 and the' is anv enlarged plan view of the,

between the inner jacket shell 15 and the outer jacket shell 16.l The shank also has the i enlargement 17 forming a shoulder 18 lor engaging thel outer jacket shell 16,

The thermostat comprises an outer tube 19 threadedly secured at 20 to the shank '3 and secured at the opposite end ,toan inner rod 21 in any suitable. manner. The tube -19 and lrod 21 arecomposed of materials having diiierentl coeicients of expansion and in the preferred form the outer tube is formed of copper, while the inner rod is made of invarsteel. ln order to permit of initially adjusting the thermostat, there is provided atube cap 22 threadedly secured to the tube 19 and aperturedto receive; the threaded end 23 of the inner rod, which 11i turn-'is secured to the cap by a nut 211. Thus yto adjust the thermostat to any `desired initial setting, the inner vrod 21 is rotated by means of a screw driver until thev cesired longitudinal adjustment isobtained','

`whereupon thenut 24:' is turned to lockthe through the passageway 25 into the hollow interior 26 ofythe shank 3ir where itibears against allever 27. The lever 27 is tulcrumed on a-pin 28, the axis of which is slightly above y* the center' line of the rod-21, thus providing fior' a relatively'small lever arm effective in operating the lever. The' lever extends longitudinally of the shank 3 and projects into the interior ofthe annular portion 1 of the valvel casing. Carried bythe free lend of the leverl smooth under surface of thevalve 29, provides supply and'jhas the further advantage that valve. v 1

-27 is a disk valve 29 which is arranded to seat' P ron an upstanding ring 30 surroundingthe gas y J. r i .outlet 7. j lliis ring is preferably oimed with a knife edge 31', which, cooperating with the an eiective means for. shutting 01T the gas y ln yorderjto insure proper seating offtlie valve upon the annular valve seat, it is de- .sirableto provide a u-niversalepivot between the valve and the lever 27. For this purpose' z j l there is provided a'yoke 32 having -a slot .K y `for receivi-ngjthe end of the lever 27 andlthe.

CTI

Sill

members are connected by a pin 34, which is secured to the yoke and passes through an aperture in the lever. Thus the valve is permitted to swivel about the axis oi the pin 34 in 'the plane 0f the lever, and it is also permitted to swing in a transverse plane by providing a slight clearance between the pin and the aperture 35. This Will insure accurate seating of the valve on the valve seat.

rllhe yoke 32 has a threadedy shank 36 for engaging the disk valve 29 and the valve is normally held against rotation by a set screw ch extends through the yoke and bears t the upper tace ot' the disk. In 'order to adjust the mechanism to close at dii'lerent tempcraturos within the water tank, the valve 2S) ma be rotatably adjusted on the threaded shank 36 and to aid in this adjustment 'there is provided an opstanding pin 38, which may easily be actuated Whei'iv the cap 9 is removed. Preferably the valve is provided With calibrations on the upper ltace thereoic which are so calculated as `to indicate directly the temperature for which the valve mechanism is set when in any predetermined position ot relative adjustment.

lt is desirable that the regulating' mechanism be capable or" operating to gradually open and close the valve according to variations in the temperature ot the thermostat, and to avoid any possible sudden or snap action oi' the valve a spring 39 is provided Which continuously urges the valve toward its closed position. As shown, this spring is a conical coiled spring, the large end ot which is arranged in an. annular recess l() in the cap '9 and the small end `of which bears on the lever 27. By arranging the spring to exert pressure directly on the valve-that is, in alignment with the axis ot the valve--it serves to counteractany spring action in the lever mechanism and thus avoids snap action oi" the valve. The spring ot course also has the furtherfunction ot always urging the valve toward closed position, but the mechanism does not depend upon the spring alone i'or this Afunction since the weight ol the valve and lever mechanism also tends to close the valve.

There is a particular advantage in comv bining'the spring actuated and gravity actuated features in one mechanism since b yniaking the valve disk 29 of great-er weight than Wouldbe necessary simply iter closing the gas outlet, it is possible to use a spring ot less tension than would otherwise be the case. lt must be ren'iembered that the valve and lever mechanism must have. sui'licient -freedom ot movement to permit the val-ve to respond to the thermostat when the latter is under the lowest'temperature conditions to which it can ever be subjected. While the device normally intended-to function only at the temperatures obtainable in a Water boiler, nevertheless it must besofdesigned as toibo capable ot' withstanding temperatures below zero on the Fahrenheit scale, because it may be subject-ed to these temperatures While in storage or in shipment. rll'hus the spring must be capable oi permitting' a considerable movement 0i the valve before it reaches collapsed posit-ion, and this means that in normal Voperation ot' the device the spring will be considerably extended and thus operating at a `tension which is considerably less than the tension when in collapsed condition. By vcombining` the Weighted valve with the spring it is only necessary to .provide in the spring sufficient tensionv to insure that it counteracts all spring inherent in the lever mechanism, and the remaining torce necec4 "try ilor inging the valve toward closed po n can be obtained by properly determining the weight ot the valve. rlhe Weighted valve also has another vfunction in that it increases the inertia of the 'moving parts and thus tends to prevent fluttering of the valve when it is adjacent the valve seat. For che reasons given above the valve 29 is preferably ot relatively great thickness so as to introduce Y the desired Weight element into the device. The valve is preferably, though not necessarily, made of brass and is provided with a small pilot orifice therethrough for always allowing a certain quantity of gas to pass `through the valve even vvhen in closed position. This pilot o 1ilice is preferably formed l by vprcfviding a bore 39 in the under side et the valve 29 which terminates a short distance rointhe upper `surface ot' the valve. The remaining' metal between the bore 39 and the upper surface is then provided with a drilled aperture, preferably oi very small diamet r, thc exact. size being predetermined in order to provide an orifice ot the proper calibration to operate the pilot light of the burner.`

As stated above the shank 3 of the housing j extends through the insulation ot the boiler and is secured to the inner boiler shell, thus Vforming a .vater seal. The shank is also integral with the annular housing tor the valve mechanism, which'niakes it inadvisable to remove the housing from the boiler. ln order to pcrmitthe removal oil the valve n'ie'chanisin tor cleaning, adjustment or other purposes, the lever 2i' is preferably termed ot two parts ft2, the line oi division being in substantial alignment With the threaded opening 8 in ther housing. The two portions oi the lever are rigidly connected together by means et the screws 43, which are so located as to be accessible when the cap il removed. Thus by removing the cap 9 and the screvvs 43, 'the valve 29 and itsassociated part-s can be readily removed trom the housing, leaving the piif'otedend 451 ot' the lever permanently secured to the housing. Y

t is to be noted in this construction that thethermostat and lever mechanism are arrangedv in substantial alignment-land thatlthe ilk? llov

lever mechanism involves only a single lever.. The ratio of the lever arms of the lever may of course be selected as desired, but in the apparatus as illustrated the leverage is twenty to one. It will also be noted that the single lever is housed for the greater part of its length in the hollow shank which eX- tends within the boiler structure thereby ob-V 44 and having upper and lower'retainers 48 between which is placed the vmaterial form-v ing the filter bed 49. The gas is conducted from the gas Cock 46 through a conduit 5() extending through the filter bed Vto asediment chamber 51 within the lowervretainerA 48. The gas then passes upwardlyl through perforations 52in vthe retainers through t e filter bed and into the gas inlet 5 of the valve mechanism. l

The apparatus as above described is preferably assembled as a unit and is then calibrated to respond vto a certain predetermined temperature of the thermostat.v In carrying out the calibration the valve 29 is adjusted to indicate a certain predetermined temperature and the thermostatic element is then placed Vto the plane of in a bath maintained at said temperature and the rod 21 is adjusted untilzthe valve 29 just engages the valve seat. Vhen this condition is obtained the lock nut 24 is tightened and the thermostat is then preferably permanently fixed in this adjustedfposition by soldering.

In the commercial production of the yregulating'device as above described it has been found'that in some instances there is a slight hum in. the mechanism when the valve is closely adjacent the valve seat, but not quite in i'irni engagement therewith, eliminated entirely vby providing means for manually holding the valve at aslight angle the valve seat so thatone side of the valve comesy in contact with the seat before the other side. Therefore it is preferable to employ a tiny spring between the lever 27 and the yoke 32 arranged on one side -of lthe axis of the valve. As shown in Figure 5, a coil spring 53 has one kend thereof inserted in a recess 54 in the outerfend of the lever 27 and the other end inserted in a recess 55 in the yoke 32. The slight tension of the spring results in until the right side of the yoke contacts with the under side of t-he lever.. When the thermostat permits the valve to move towards Hmoved therewith Y This may be.

Vvalve casing..

thetilting ofthe disk valve closed position, one side of the valve comes into engagement with the. seat before the other and this prevents any noise in the meehlanism'no matter in what position the valve is adjusted. i

lhat we claim as our invention is:

l. A gas regulator for water heatersY comprising a casing having a gas inlet port,4a gas outlet port at the Vbottom portion thereof and an annular ring surrounding said outlet port forming a valve seat, said casing having aghorizontally projecting hollow shank, a single lever pivoted to said shank having' a long arm extending horizontally withintlie shank, and a short arm extending transversely thereof, a disk valve depending from andv pivotally carried by the long arm, a cap of larger diameter than said valve arranged above said valve, and a spring between said cap and valve arranged to urge the latter toward closed position.

2. A gas regulator for water heaters comprising a hollow valve casing havingl inlet and out-let ports, a valve seat surrounding said outlet port, a disk valve adjacent said valve seat, a hollow shank extending laterally of said valve casing, a lever pivoted to said shank andextendingwithin the same towards said valve casing, a vseparate-mem.- ber removably secured to said lever Vand pivotally connected to having an aperture-arranged to permit removal of said valve and said separate member as a unit, and a cap for closing lsaid aperture.

3. In a gas regulatorffor water heaters,

the combination with Va'valve. casing having a laterally extending shank projecting therefrom, of a lever pivoted to said shank and extending within the same-toward said valve casing, saidcasing having an opening therein, a cap for said opening, a separate member within said valve casing removably secured toA said lever and forming v a continuation thereof, .and a valve .pivotally connected. to said rseparate rmember through the-opening in said 4f. A gas regulatorfor waterheaters-comprising a casing, a valve seat, a lever, means responsive-to'temperature changes for moving said lever-toward and away from said valve seat, a disk valve pivotally mounted on the lever, and a spring between said lever and valve offset from the axis of the latter and adapted to normally maintain said valve Vat an inclination to the valve seat. j

In testimony whereof we affix our signatures.

AFRANK W. sHUnLL.'

nLMnR n. Lnnnnrrnn. ,frnoMAs J. Tomar. .y

and adapted to be re- LTI said valve, said 'casing 

